To find the perimeter of this green figure, let's break it down by identifying all of the line segments and calculating their total length.

Step-by-Step Solution:

1. Identify all the sides in the figure:

   • The top side: $12 \, \text{cm}$
   • The left side (two segments combined): $4 \, \text{cm} + 2 \, \text{cm} = 6 \, \text{cm}$
   • The long diagonal side: $26 \, \text{cm}$
   • The bottom right segment adjacent to the long diagonal side: $4 \, \text{cm}$

2. Sum the lengths of each side:

   • Top side = $12 \, \text{cm}$
   • Left side = $6 \, \text{cm}$
   • Diagonal side = $26 \, \text{cm}$
   • Bottom right segment = $4 \, \text{cm}$

3. Calculate the perimeter: $\text{Perimeter} = 12 + 6 + 26 + 4 = 48 \, \text{cm}$

Final Answer:

Perimeter = 48 cm

Would you like further details or explanations on any steps?

Here are 5 related questions to expand your understanding:

1. How would the perimeter change if the diagonal side were extended by 5 cm?
2. What is the area of this figure?
3. How would you find the length of the hypotenuse in the inner right-angled triangle?
4. If the figure was scaled by a factor of 2, what would the new perimeter be?
5. How can we use the Pythagorean theorem to confirm the length of the sides in the figure?

Tip: When working with irregular shapes, break them down into familiar geometric shapes to simplify calculations.